Forum for Science, Industry and Business

Solutions to stop fishermen returning dead and dying marine animals back into sea

28.10.2004

Scientists have produced a potential solution to a problem fishing activity which costs the industry millions of pounds and has a major impact on the marine environment worldwide.

A team from the University of Newcastle upon Tyne, writing in the academic journal Marine Policy, say fishermen should be given incentives not to return unwanted fish and other marine animals – known as ’discards’ – back into the sea after they are caught in their trawlers’ nets.

The study focused on the North Sea, which is bordered by Norway and the European Union countries Belgium, Denmark, France, Germany, Holland and the UK. However, there are plenty of other places in the world, such as North America, which have similar problems with discards. The findings of the research are expected to inform European Union policy about discards. Discards are mainly young or damaged fish or sea life that cannot be sold because there is no market for them, or, if taken back to shore, would exceed the fishers’ catch quota.

Almost one million tonnes in weight and many millions of pounds worth of discards – including haddock, cod, whiting and flatfish like plaice, sole and dab - are thrown back into the North Sea after they are caught in trawlers’ nets every year, and they are usually dead by the time they are returned to the water. This quantity equates to nearly one-third of the total weight of fish brought ashore, and one-tenth of the estimated total of biomass of fish in the North Sea.

For the study, the Newcastle University research team examined the political conditions, management strategies, behavioural attitudes and economic incentives associated with discarding. They analysed a variety of data sources, including industry communications, debate transcripts and scientific and technical texts.

The team, from Newcastle University’s School of Marine Science and Technology and the School of Geography, Politics and Sociology, estimate that discarding will have severe long-term economic consequences. The discarding of juvenile fish has been a major factor in depleting the North Sea stocks and continues to threaten the long-term sustainability of fish populations.

Although the full extent of the consequences on the marine environment are not known, discards are considered to have contributed to the growth of several seabird populations such as the fulmar and the lesser black-backed gull. It is estimated that North Sea discards could potentially support over six million seabirds.

The team is calling for fisheries management authorities to restrict access to certain areas of the sea where the unwanted fish are likely to gather, and for gear such as fishing nets to be adapted so that they may be more selective. Under the proposals, those who comply with the rules would be allocated more fishing days at sea as an incentive.

The research paper’s lead author, Tom Catchpole, said: "Millions of pounds of potential fish landings are lost through discarding. For the improvement of stocks like whiting, haddock and plaice it is essential that discarding be reduced. "The main problem is that it would initially be at a cost to fishermen. Direct compensation has not been forthcoming, therefore, incentives must be generated by alternate means.

"Granting better access to fishing grounds or allowing more fishing time to those who fish more selectively are methods that have proved successful. Once these incentives are created, fishermen’s knowledge should be used to develop acceptable fishing techniques and short-term losses would quickly become long-term gains."

Co-author, Professor Chris Frid, said: "For hundreds of years, people in the fishing industry have been aware of the need to reduce the number of discards, and they are committed to achieving it. The problem has always been – how?

"Although part of the solution could be to close off certain problem areas, enforcing this rigidly would be difficult as the small fish tend to move around. Authorities need to take a flexible approach so that there is minimal disturbance to day-to-day fishing activities but maximum benefit to the ecosystem."

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